This invention concerns a.c. circuits including variable resistance devices.
In high frequency impedance measuring equipments there is considerable difficulty in producing a variable or switched resistance path which does not have errors caused by capacitance between switch contacts and inductance of the lengthy leads necessary to make the appropriate connections.
It is accordingly an object of the present invention to provide, in an a.c. circuit, a variable resistance path in which errors due to stray capacitance or inductance are reduced in relation to hitherto known arrangements.